Stuck in the Middle: Climbing my way out of the plot hole

Good afternoon, all. This is KGG coming at you from the kitchen table where I have been surfing the net and doomscrolling because I'm avoiding the pain of having to do tricky mental somersaults regarding my book.

You see, I was coasting along just fine, getting in 2,500 words at a clip, but then I hit the 30% mark and now I'm stuck. I couldn't see the forest. Didn't get an aerial view of the landscape. And I'm lost. Basically, I didn't outline far enough ahead because I wasn't sure how events would play out. 

So I gotta fix this.

Like all my tomes, this is a murder mystery. And while I have planned the crimes, and I solved the protagonist in the room with the weapon part of my plot, I have not figured out how my characters get to the magical end where everything is revealed. I know there are some authors who write as if they are on a journey and just go with the flow wherever the characters takes them, and I so want to be that person. But I'm the dope who decided on a dual narrative timelines, so I have two characters who need to be proactive in solving the crimes. Which means I can't simply tag along for the ride. I have to unwind the knotted mess of my plot arcs.

Therefore, I must stop writing and think.

So how does one do that? 

First, I get out a notebook and a pen. Kick it old school.

Then, I open up my book in Scrivener and see where I start the story and where I intend to end it. I write these two points on a piece of paper, like a vertical number line. Beginning. End. I always know how my books end.

And then I jot down the plot twists I want to hit. The moments that make you gasp at the end of a scene. I write them in the plot line.

And then, on another timeline, I map out the crime in chronological order. In this case, the crime happened thirty years ago. I can add what suspects were involved at what point. This allows me to see what my modern protagonist has to uncover so that she can properly solve the murder mystery, and so my readers are not scratching their heads at the conclusion.

And then I have to thread the two timelines together.

But, wait! I have two protagonists. So while my female protagonist is doing A, my male protagonist is doing B. This is actually where I am truly stuck, especially since they both need a proper arc.

But once I have listed the events that need to happen in order for mystery to be solved, I can see how my characters can work to make this happen. 

You'd think I would have worked this stuff out long before I start writing the first scene, but often times I haven't discovered my story yet. So, easier said than done.

Anyway, I hope this helps someone out there climb out of their plot hole.

And if you have tips or strategies that you think might be helpful, pass them along. I can always use the help.